Process of making cotton textiles water-absorbent and rotresistant



Patented Aug. 31,1948

PROCESS OF MAKING COTTON TEX- TILES WATER-ABSOBBENT AND BOT- RESISTANT John David Reid and George C. Daul, New orleans, La., assignors to the United States of America as represented by the Secretary of Agriculture No Drawing. Application September 10, 1946, Serial No. 696,024

(Granted under the act of March 3, 1883, as

3 Claims.

This application is made under the act of March 3, 1883, as amended by the act of April 30, 1928, and the invention herein described, if patented, may-be manufactured and used byor amended April 30, 1928; 370 0. G. 757) and therefore may be used as a waterproof wall. The water-absorbent property renders the textile useful in the production of toweling, surgical bandages and sponges, and the like.

duction of such articles as tents, water pressure hose, and the like, since the cloth due to swelling of the yarn becomes leak proof when wet.

for the Government of the United States of 5 In ease t metallic t employed is a salt of America for governmental purposes without the copper, it is unexpected that the resulting rotpayment tons of any royalty thereon, DIOOf textile is highly swellable. The copper- This invention relates to textiles, and has cellulosic salt is itself almost entirely insoluble among its objects the production of cotton textiles in W t when t w d be exp t d t the which are swellable when wetted, highly water textile with the copper substituted carboxyabsorbent and rot resistant. methyl groups would swell'but little.

In general, according to the invention, a cot- The following examples exhibit the invention ton textile is soaked with monochloracetic acid in ter d w-L I and then treated with a solution of an alkali EXAMPLE I m t hy rox d s h as s d um hyd e, va y- Three skeins of similar No. 12 soft cotton seine ing in concentration between percent to 50 twine. (samples numbered 1, 2 and 3) were made Percent, to give a resulting textile containing up and treated with boiling ethyl alcohol to reabout one carboxymethyl substitueut P 40 to move waxes. The wax extraction is not neces- 5 glucose units the higher carboxymethyl sary but helps to insure good penetration. The stitution going with the higher concentration of 20 skems were then soaked in a Solution of NaOH whlch is swenable when Wettedrand is monochloracetic acid, pressed out, and mercerw t r abso be t, t e d ee o s ty and ized under tension with, respectively, 20%, 24%, absorbency being controlled by the strength of 1.23% sodium hydroxide fo a period of one the hydroxide used and consequent degree of carn boxymethyl substitution. The textile can be 25 The samples werethen thoroughly washed and rendered rot resistant by treating it further with t t t an excess of a 0% solution of SOlutiOXlS Of certain metallic salts in such manper sulfate and again washed Part of each that insoluble metal Salts of the b' ysample was analyzed for copper to determine the methyl groups present in the textile are formed. ca -boxy] content, The ample were then ex- A salt which yields copper ions in solution thus posed t the action of micro-organisms by t pr du t pp r sa ts of the carboxymethyl weighting and submerging in the water of Bayou g ps is qu te Sat o y H0WeVe1,0ther 1118- St. John, New Orleans, Louisiana. The average tallic salts, such as those which yield iron, siltemperature of the bayou was 58 F. Control ver, nickel, mercury, lead or aluminum ions, may samples of untreated twine and twine treated be employed. Treatment with a metallic salt with copper napht'henate were also exposed and also affects the manner of swellability, as later portions of the samples were removed at various will be shown. time intervals for testing. Tensile strength in The swellable and water-absorbent fabrics of lbs. per twine were determined, the results bethe invention, with or without treatment to rening given in Table 1.

Table 1 Tensile strength, lbs. per twine NsOH cu Twine 88mph percent percent Expose Exposed Exposed Exposed Exposed Exposed Dwk. 2wks. iwks 6wks. 8wks. 11 wks Untreated control 0.00 so. 2 1a. 4 00. 0 Cu nsphthenate control. 1.00 34. 1 36. 8 29.8 22. 9 15. 9 6.7 No. 1 20 0. a5 a0. 2 30.8 20. s 15. 7 14. 5 3. 0 24 0.80 31.0 29.6 19.3 13.1 7.3 2.9 28 2.20 28.6 27.2 18.7 14.4 7.8 3.2

der them rot-resistant, are useful in the pro- EXAMPLE II To show the efiect of varying themetallic salt employed, 21 skeins of cotton thread were soaked in 40% monochloracetic acid overnight with a wetting agent to aid penetration. Seven skeins were mercerized with 25% sodium hydroxide, seven with 28% sodium hydroxide, and seven with 30% sodium hydroxide for a period of one hour. The skeins were then washed thoroughly with the addition of a, small amount of acid to aid in obtaining neutrality. One each of the seven skeins of each group was treated with an excess 01' a copper sulfate solution, a ferric chloride solution, a silver nitrate solution, a nickel chloride solution, a mercuric chloride solution, a lead acetate solution, and an aluminum sulfate solution to give complete metallic substitution in the carboxymethyl groups present. After treatment, the samples were washed and dried. Sets of threads taken from the samples were then buried in soil containing highly active cellulosedestroying organisms and samples were removed at various intervals of time for testing. The results are given in Table 2.

Table 2 absorbency being based on the weight or the dryyarn.

Small portions of sample No. 4 and sample No. 5 were further treated with an excess of copper sulfate and analyzed. They contained 0.5 percent and 0.72. percent or copper, corresponding to carboxymethyl substituents in the ratio one to 40 and one to 20 glucose units, respectively.

Sample No. 6 swelled so much that its usefulness Tensile strength, lbs. per thread Metallic salt used $2 E d E E d E d E d xpose xpose xpose xpose xpose Exposed E sed 0 wk. 1 wk. 2 wks. 3 wks. 4.5 w 7.5 wks. 10mins.

15. 5 0. 0 15. 7 8. 2 0. 0 28 16. 2 6. 7 0. 0 16. 5 7. 2 0. 0 25 14. 7 5. 4 0. 0 28 15. 6 5. 2 0. 0 30 14. 8 8. 7 0.0 25 15.5 15.8 15.0 13.0 11.2 0.0 23 15. 6 14. 6 l5. 1 13. 9 11. 4 7. 0 0.0 30 14. 9 13. 8 12 6 12. 8 12. 2 6. 5 0. 0 25 17. 0 6. 6 0. 0 28 16. 2 8. 4 0. 0 30 15. 0 7. 6 0. 0 25 16. 3 15. 8 16. 1 16. 7 16. 7 7. 5 0. 0 28 16. 1 l6. 7 16. 5 16. 4 17. 4 16. 3 0. 0 30 15. 2 16. 6 16. 6 17. 3 17. 3 16. 7 0. 0 25 17. l 16. 5 l2. 7 0. 0 28 15. 9 l7. 3 l0. 4 7. 9 0. 0 30 14. 8 16. 2 11. 5 7. 4 0. 0 25 16. 2 7. 1 0. 0 H 15. 9 5. 4 0. 0 30 16. 4 6. 3 0. 0

Exmta III To show the effects of the treatment relating to water-absorbency and swellability, three skeins of cotton yarn were soaked in a 40% solution of monochloracetic acid containing a. wetting agent to assure good penetration and were then treated with 32%, 35% and sodium hydroxide soluresistancy. The table also shows that even as tion, respectively, for one-half hour. The samples are numbered 4, 5 and 6 in Table 4. Part of the sample treated with the 40% sodium hydroxide solution was further treated with an excess oi! copper sulfate solution (numbered 7 in the table), and it contained 2.4% copper which indicates that there is approximately one carboxyl group per every 5 glucose units of the cellulose.

Various samples were tested for water absorption by soaking them in water for 24 hours and then centrifuging at 1850 times gravity for 20 little as approximately one carboxyl group per 40 glucose units, as in the case of sample No. 4, imparts good swelling properties.

.Not' only can yarns and threads be processed according to the invention, but cotton cloth may also be so processed, as for example, by treating it with monochloracetic acid and then mercerizing it with or without tension, followed, if desired, by the treatment with metallic salts in a manner similar to the treatment heretofore set forth relative to the yarns and threads.

Table 4 gives the results obtained by treatment of a number of samples of khaki-dyed. herringbone twill. The permeability to air was measured on a standard machine, and the results are given in cubic feet of air passed per minute through a square foot of the material. The samples were also tested on the Enter hydrostatic pressure machine with a 4 /2" circular opening, under a 6" pressure head for 5 minutes, and the milliliters of water passing through the cloth measured.

1 Copper equivalent 1.43. I Copper equivalent 3.02.

Mercerization of the cloth in a conventional manner (sample N0. 9) permanently swells the cloth fibers so that both air and water permeability are reduced somewhat over those of the cloth not treated (sample No. 8). Increasing the strength of the sodium hydroxide solution used,

Having thus described the invention, what is claimed is:

1. A process comprising impregnating a cotton textile with chloracetic acid, treating the impregnated textile with a solution of an alkali metal hydroxide ranging in concentration between and 50% to give a fabric having carboxymethyl substituents in the ratio of one to from 40 to 5 glucose units, and then treating the textile with a solution of a salt which yields metal ions in the solution and produces a non-soluble metal salt of the carboxymethyl groups, the said salt being selected from the class consisting of salts of copper, iron, silver, nickel, mercury, lead and aluminum.

2. The process of claim 1 in which the salt is a salt of copper.

3. The process of claim 1 in which the salt is copper sulfate.

however, (sample No. 10 and sample No. 11)

greatly decreases the water permeability. The air permeability is, however, somewhat increased because the dry cloth, when mercerized with the higher strength sodium hydroxide solution, is stiffer due to the greater amount of carbonmethyl groups added. Treating with copper salt (sample No. 12 and sample No. 13) tends to increase water permeability over corresponding samples not so treated, because the treatment tends to render the cloth porous.

JOHN DAVID REID. GEORGE C. DAUL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number 

